Benefits of incorporating atipamezole in medetomidine-ketamine anaesthesia in pigeons

Smooth recovery from anaesthesia is vital in the restrain and surgery of animals, including birds. In birds, ketamine is often combined with alph2 agonists, which are respiratory depressants to ensure safe or balanced anaesthesia. The timing of administration and the effect on recovery for specific alhpa2 agonist antidotes in birds have not been widely investigated. This study was conducted to assess the reversal effects of atipamezole administered at the first sign of recovery on medetomidine-ketamine anaesthesia in pigeons. Twelve pigeons were administered with 1) medetomidine as a pre-anaesthetic at 120 μg/Kg, followed 10 min later by ketamine at 30 mg/Kg (MK group) and 2) Medetomidine and ketamine followed by atipamezole (MKA group). Medetomidine produced moderate sedation within 3.08 ± 0.21 min. Medetomidine-ketamine produced smooth and excitement free induction of anaesthesia in pigeons. Ketamine produced surgical anaesthesia within 4.58 ± 0.68 min. Duration of anaesthesia was 55.79 ± 4.51 min. Vital parameters - pulse rate, respiratory rate and cloacal temperatures decreased significantly after premedication as well as during anaesthesia in the MK group which served as the control. The MKA group significantly increased (P < 0.001) the pulse rate, respiratory rate and cloacal temperature compared to MK group that indicated a reversal effect of atipamezole. Atipamezole incorporated into medetomidine-ketamine anaesthesia produced quicker recovery (P < 0.01) in 44.17 ± 3.01 min compared to 62.5 ± 4.64 min in MK group. Atipamezole significantly (P < 0.05) decreased the duration of anaesthesia and duration of other recovery indices. Recovery was generally smooth in all birds. Atipamezole at 60 μg/Kg produced rapid recovery from anaesthesia 18 min earlier than MK group.